1. Field of the Invention
The present invention relates to a display device integrated with touch screen, and more particularly, to a color filter substrate for a display device integrated with touch screen.
2. Discussion of the Background Art
There is a display device where electrodes are alternately arranged at one of upper and lower substrates and a liquid crystal is between the substrates thereby display images, and particularly, there is a display device integrated with touch screen in which touch electrodes are built.
The touch screen-integrated display device integrated with touch screen is fabricated by attaching a color filter substrate having a color filter array and a TFT (thin film transistor) substrate having a thin film transistor array with a liquid crystal therebetween, and displays images by adjusting light transmittance of liquid crystal that has dielectric anisotropy.
The TFT substrate includes a TFT, a pixel electrode and a common electrode in each cell region that is defined by crossing of gate and data lines on a substrate, and the color filter substrate includes a black matrix blocking light leakage, and red, green and blue color filters with black matrix thereamong.
The touch screen-integrated display device according to the prior art is operated in a display driving mode or touch driving mode with a time division method. That is, when the driving mode of the display device is the display driving mode, the pixel electrode of the TFT substrate is supplied with a data signal, and the common electrode is supplied with a common voltage that is as a reference voltage when operating the liquid crystal, thus the liquid crystal is rotated and adjusts light transmittance according to an electric field produced by the data signal of the pixel electrode and the common voltage of the common electrode, and thus gray level is realized. When the driving mode of the display device is the touch driving mode, the pixel electrode or the common electrode is divided and utilized as a touch electrode, and thus touch position by user's input is sensed.
However, since the touch electrode is formed by diving the pixel electrode or common electrode at the TFT substrate in the prior touch screen-integrated display device, circuit design is difficult, and achieving large size is difficult because of increase of time constant.